CREATE PROCEDURE dbo.who 
@who char(30 ) OUTPUT
AS
SELECT  @who=CURRENT_USER
GO

Public Sub Who()
Dim cnn As ADODB.Connection
Dim cmd As ADODB.Command

Dim CodeStr As String

Set cnn = New ADODB.Connection
Set cmd = New ADODB.Command
  
Set cnn = CurrentProject.Connection
Set cmd.ActiveConnection = cnn

With cmd
.CommandText =  "dbo.who" 
.CommandType = adCmdStoredProc
.Parameters.Append .CreateParameter( "@Who" , adChar, adParamOutput,  30 )
.Execute
CurrentUser = Trim(.Parameters( "@Who" ))
End With

Set cmd = Nothing
cnn.Close
Set cnn = Nothing
End Sub

Private Sub Form_Open(Cancel As Integer)
....
Who
....
End Sub